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ISSN: 2056-9890

Crystal water as the mol­ecular glue for obtaining different co-crystal ratios: the case of gallic acid tris-caffeine hexa­hydrate

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aUniversity of Malta, Msida, MSD 2080, Malta
*Correspondence e-mail: ulrich.baisch@um.edu.mt

Edited by A. J. Lough, University of Toronto, Canada (Received 9 March 2018; accepted 18 March 2018; online 27 March 2018)

The crystal structure of the hexa­hydrate co-crystal of gallic acid and caffeine, C7H6O5·3C8H10N4O2·6H2O or GAL3CAF·6H2O, is a remarkable example of the importance of hydrate water acting as structural glue to facilitate the crystallization of two components of different stoichiometries and thus to compensate an imbalance of hydrogen-bond donors and acceptors. The water mol­ecules provide the additional hydrogen bonds required to form a crystalline solid. Whereas the majority of hydrogen bonds forming the inter­molecular network between gallic acid and caffeine are formed by crystal water, only one direct classical hydrogen bond between two mol­ecules is formed between the carb­oxy­lic oxygen of gallic acid and the carbonyl oxygen of caffeine with d(DA) = 2.672 (2) Å. All other hydrogen bonds either involve crystal water or utilize protonated carbon atoms as donors.

1. Chemical context

Gallic acid and its derivatives are widely known compounds in the pharmaceutical and chemical industry (Nayeem et al., 2016[Nayeem, N., Asdaq, S. M. B., Salem, H. & AHEl-Alfqy, S. (2016). J. App. Pharm. 8, 213.]; Clarke et al., 2011[Clarke, H. D., Arora, K. K., Wojtas, Ł. & Zaworotko, M. J. (2011). Cryst. Growth Des. 11, 964-966.]). One such example is the dietary polyphenol found in Choerospondiatis fructus, a Mongolian medicinal herb used to treat conditions such as angina pectoris (Zhao et al., 2007[Zhao, X., Zhang, W., Kong, S. J., Zheng, X., Zheng, J. & Shi, R. (2007). J. Liq. Chromatogr. Related Technol. 30, 235-244.]). Lately, it has gained a lot of attention as a versatile component in crystal enineering, in particular with regards to co-crystallization and hydratation. Gallic acid could represent an entire microcosm of the special challenges and opportunities afforded by hydrates (Clarke et al., 2011[Clarke, H. D., Arora, K. K., Wojtas, Ł. & Zaworotko, M. J. (2011). Cryst. Growth Des. 11, 964-966.]) as it contains two of the most ubiquitous functional groups present in APIs: carb­oxy­lic acids and phenols. As part of a series of co-crystallization experiments in which both caffeine and gallic acid were used as coformers, single crystals of hydrated gallic acid and caffeine GAL3CAF·6H2O in the ratio gallic acid:caffeine:water of 1:3:6 were obtained and characterized by single-crystal X-ray diffraction. The crystal structure is reported herein and compared to the different hydrated forms of this co-crystal GALCAF·0.5H2O reported elsewhere (Clarke et al., 2010[Clarke, H. D., Arora, K. K., Bass, H., Kavuru, P., Ong, T. T., Pujari, T., Wojtas, L. & Zaworotko, M. J. (2010). Cryst. Growth Des. 10, 2152-2167.]). The crystal structures differ greatly because of the different stoichiometry of the coformers. The different number of water mol­ecules is necessary to act as structural glue, thereby facilitating crystallization.

2. Structural commentary

The asymmetric unit of the co-crystal GAL3CAF·6H2O consists of three independent caffeine mol­ecules and one gallic acid mol­ecule as well as six hydrate water mol­ecules. Gallic acid can be described as a thrice-substituted benzoic acid with hydroxyl groups in both the meta and para positons. Caffeine consists of a purine backbone with carbonyl substit­uents at positions 2 and 6 (C26, C28, C46, C48, C66, C68) and methyl groups connected to three out of four nitro­gen atoms (Fig. 1[link]).

[Scheme 1]
[Figure 1]
Figure 1
Mol­ecular structure of the GAL3CAF·6H2O showing the labelling scheme and displacement ellipsoids drawn at 50% probability level.

Bond distances of the aromatic rings and substituents of both types of mol­ecules lie within the expected ranges and exhibit the usual lengths for aromatic, double or single homo- or heteroatomic bonds. Only one nitro­gen atom on each of the three caffeine mol­ecules can act as a hydrogen-bond acceptor (N23, N43, N63) with the protonated carbon in the five-membered ring (C22, C42, C62) acting as a weak hydrogen-bond donor. Every mol­ecule exhibits weak intra­molecular inter­actions (Steiner, 2002[Steiner, T. (2002). Angew. Chem. Int. Ed. 41, 48-76.]). Whereas gallic acid forms inter­moleclar bonds between two adjacent hydroxyl substituents [O11—H11⋯O10, d(DA) = 2.709 (2) Å], the caffeine mol­ecules form weak inter­actions between two of three methyl carbons and two carbonyl oxygen or backbone nitro­gen atoms, namely C31, C33, C51, C53, C71, C73 as well as O32, N43, O54, O72, and O74. Distances range between 2.71 and 2.95 Å. In comparison, the corresponding intra­molecular hydrogen-bonding inter­actions in the published GALCAF·0.5H2O structure reported in the Cambridge Structural Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) with code MUPNOB (Clarke et al., 2010[Clarke, H. D., Arora, K. K., Bass, H., Kavuru, P., Ong, T. T., Pujari, T., Wojtas, L. & Zaworotko, M. J. (2010). Cryst. Growth Des. 10, 2152-2167.]) have distances of d(D⋯A)gallic acid = 2.743 (2), 2.712 (2) Å and d(DA)caffeine of 2.78–2.71 Å.

3. Supra­molecular features

As a result of the limited number of hydrogen-bond donors and acceptors in both gallic acid and caffeine, the packing strongly depends on (i) the concentration of each of the components in solution as well as (ii) other experimental conditions such as other components in solution, temperature, pressure, etc. In fact, there is a large difference in the way both mol­ecules pack in the crystal lattice.

The crystal structure of GALCAF·0.5H2O (Clarke et al., 2010[Clarke, H. D., Arora, K. K., Bass, H., Kavuru, P., Ong, T. T., Pujari, T., Wojtas, L. & Zaworotko, M. J. (2010). Cryst. Growth Des. 10, 2152-2167.]) has a 1:1:0.5 ratio of gallic acid, caffeine and water mol­ecules. Both mol­ecules form hydrogen-bonded tapes that are built by COO—H⋯N and O—H⋯O inter­actions [O⋯N = 2.705 (2) Å and O⋯O = 2.703 (2) and 2.750 (2) Å] formed between the hydoxyl substituents on gallic acid mol­ecules and the carbonyl moieties of adjacent caffeine mol­ecules. These tapes are then cross-linked by water mol­ecules that hydrogen-bond with the third hy­droxyl group in each gallic acid mol­ecule [O⋯O = 2.857 (1) Å]. The water mol­ecules facilitate the formation of bilayers that stack in an ABAB manner sustained by ππ inter­actions. The distances between these layers of mol­ecules can be calculated from the distances between the centroids of the aromatic rings of the two mol­ecules and range from 3.3742 (14) to 4.3402 (14) Å. The ratio between classical hydrogen-bond donors and acceptors is 4:4 (four donors and one acceptor on the gallic acid mol­ecule and three acceptors on the caffeine mol­ecule).

The different balance of gallic acid and caffeine in GAL3CAF·6H2O affects the donor/acceptor ratio significantly. There are still only four classical hydrogen-bond donors deriving from the hydroxyl groups on gallic acid, but ten hydrogen-bond acceptors (three on each caffeine and one on gallic acid). This discrepency is equilibrated by inclusion of additional solvent water mol­ecules into the crystal structure. These act as structural glue enabling crystallization in different stoichiometries and thus, compensating for the above imbalance. The water mol­ecules provide the additional hydrogen bonds required to form a crystalline solid. Thus, the majority of hydrogen bonds forming the inter­molecular network between gallic acid and caffeine are formed by crystal water (Table 1[link]) with d(DA) ranging from 2.643 (2) to 3.011 (2) Å. Direct classical hydrogen bonding between non-carbon atoms can only be observed between the carb­oxy­lic oxygen of gallic acid (O1) and the carbonyl oxygen of caffeine (O32) with d(D⋯A) = 2.672 (2) Å (Fig. 2[link]). Additionally, there is a significant number of weak C—H⋯O inter­actions present between gallic acid mol­ecules and caffeine mol­ecules and between caffeine mol­ecules themselves (Table 1[link]). One of these inter­actions is between carb­oxy­lic acid and a carbonyl oxygen via hydrogen bonding that is almost parallel to an inter­action between the carbonyl oxygen (O2) of the carb­oxy­lic group in gallic acid with the adjacent proton of a caffeine methyl substituent (C31) d(D⋯A) 3.326 (3) Å. Another C—H⋯O inter­action is notable as it forms a linear chain connecting all caffeine mol­ecules to each other (Fig. 3[link]). These are formed between the only protonated carbon atom in the purine backbone (C22—H22, C42—H42, C62—H62) and the carbonyl oxygen of the next caffeine mol­ecule (O32, O52, O72) with donor–acceptor distances ranging from 3.119 (3) to 3.227 (3) Å. O12 links gallic acid mol­ecules to these chains via additional weak C—H⋯O inter­actions to C30 [d(D⋯A) 3.247 (3) Å] and C42 [d(D⋯A) = 3.254 (3) Å]. A comparable inter­action between the protonated carbon of the purine ring does not exist in the GALCAF·0.5H2O structure.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O32i 0.85 (3) 1.86 (3) 2.672 (2) 161 (3)
O10—H10⋯O104 0.86 (4) 1.79 (4) 2.643 (2) 174 (4)
O11—H11⋯O10 0.83 (3) 2.32 (4) 2.709 (2) 109 (3)
O11—H11⋯O102 0.83 (4) 1.88 (4) 2.680 (2) 161 (3)
O12—H12⋯O100i 0.86 (3) 1.86 (3) 2.702 (2) 166 (3)
O100—H10C⋯O105 0.83 (4) 2.07 (4) 2.851 (3) 157 (4)
O100—H10D⋯O10 0.82 (4) 2.74 (3) 3.286 (2) 126 (3)
O100—H10D⋯O102 0.82 (4) 2.02 (4) 2.798 (3) 158 (3)
O101—H10I⋯N43ii 0.94 (4) 1.97 (4) 2.898 (3) 170 (3)
O101—H10J⋯O100 0.88 (4) 2.09 (4) 2.960 (3) 170 (4)
O102—H10A⋯O101iii 0.89 (4) 1.87 (4) 2.754 (3) 169 (4)
O102—H10B⋯O103 0.85 (4) 1.85 (4) 2.691 (3) 173 (3)
O103—H10K⋯O34iv 0.78 (5) 2.06 (5) 2.832 (3) 168 (5)
O103—H10L⋯N23v 0.84 (5) 1.99 (5) 2.823 (3) 168 (4)
O104—H10G⋯O1vi 0.91 (3) 2.50 (3) 3.011 (2) 116 (2)
O104—H10G⋯O105 0.91 (3) 2.03 (3) 2.857 (3) 151 (3)
O104—H10H⋯O74vi 0.93 (5) 2.00 (5) 2.924 (2) 171 (4)
O105—H10E⋯O74ii 0.86 (5) 2.11 (5) 2.952 (2) 169 (4)
O105—H10F⋯N63 0.88 (4) 1.92 (4) 2.798 (2) 173 (4)
C22—H22⋯O72vii 0.97 (3) 2.38 (3) 3.227 (3) 146 (2)
C30—H30C⋯O12vii 0.98 2.71 3.247 (3) 115
C31—H31C⋯O2vi 0.98 2.40 3.326 (3) 158
C42—H42⋯O12viii 0.92 (3) 2.45 (3) 3.254 (3) 146 (3)
C42—H42⋯O72 0.92 (3) 2.66 (3) 3.136 (3) 113 (2)
C62—H62⋯O52vii 0.96 (3) 2.24 (3) 3.119 (3) 151 (3)
Symmetry codes: (i) [x, -y+1, z-{\script{1\over 2}}]; (ii) [x, -y+2, z+{\script{1\over 2}}]; (iii) x, y-1, z; (iv) [x+1, -y+1, z+{\script{1\over 2}}]; (v) x+1, y, z; (vi) [x, -y+1, z+{\script{1\over 2}}]; (vii) x-1, y, z; (viii) x, y+1, z.
[Figure 2]
Figure 2
Crystal packing of GAL3CAF·6H2O viewed along b. Hydrogen-bonding inter­actions (Table 1[link]) are shown as red dashed lines.
[Figure 3]
Figure 3
Crystal packing of GAL3CAF·6H2O. Hydrogen-bonding inter­actions (Table 1[link]) are shown as blue dashed lines.

The crystal structure of GAL3CAF·6H2O can be described as having two types of mol­ecular layers connected via hydrogen-bonding inter­actions with solvent water mol­ecules. Layers consisting solely of caffeine mol­ecules are stacked alternately with layers composed of caffeine and gallic acid mol­ecules (Fig. 4[link]). The distances between the centroids of the aromatic rings are within the significance range at 3.231 (13) and 4.5028 (13) Å. Thus π-stacking of the aromatic rings is both stronger and weaker in places.

[Figure 4]
Figure 4
Crystal packing of GAL3CAF·6H2O viewed along a. Hydrogen-bonding inter­actions are shown as red dashed lines.

The discussed crystal structure provides a good representation of the large impact of weak C—H⋯O inter­actions and of how solvent mol­ecules can play a crucial role in the formation of crystal structures. All our attempts at obtaining a solventless co-crystal with the same stoichiometry have failed so far.

4. Synthesis and crystallization

The crystals were obtained as a by-product in a reaction aiming for the synthesis of a lanthanide salt. Gel crystallizations were carried out in order to slow the crystallization process down. This technique involves a piece of glassware that allows two solutions to diffuse through a (tetra­methyl­orthosilicate) gel medium. The two sets of reagents then react when they eventually diffuse through the gel. Tetra­methyl­orthosilicate gel (10%) was prepared freshly from 7 mL in 63 mL distilled water using Na2CO3 to make the gel approximately pH 8, and left to set overnight using U-tubes. Solutions were put into the two reservoirs: one contained caffeine (1 mmol, 0.2 g), while a solution containing an excess gallic acid and lanthanide was in the other.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. Methyl H atoms were refined as riding (C—H = 0.98 Å with Uiso(H) = 1.5Ueq(C).

Table 2
Experimental details

Crystal data
Chemical formula C7H6O5·3C8H10N4O2·6H2O
Mr 860.81
Crystal system, space group Monoclinic, Pc
Temperature (K) 150
a, b, c (Å) 16.5434 (3), 6.79456 (11), 18.1390 (4)
β (°) 110.865 (2)
V3) 1905.21 (7)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.12
Crystal size (mm) 0.66 × 0.37 × 0.06
 
Data collection
Diffractometer Rigaku Oxford Diffraction Xcalibur, Atlas, Gemini ultra
Absorption correction Analytical (CrysAlis PRO; Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.])
Tmin, Tmax 0.946, 0.994
No. of measured, independent and observed [I > 2σ(I)] reflections 38532, 9519, 8931
Rint 0.029
(sin θ/λ)max−1) 0.695
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.086, 1.04
No. of reflections 9519
No. of parameters 645
No. of restraints 2
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.24, −0.23
Absolute structure Flack x determined using 4000 quotients [(I+)−(I)]/[(I+)+(I)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.])
Absolute structure parameter −0.1 (2)
Computer programs: CrysAlis PRO (Rigaku OD, 2015[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]).

Supporting information


Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Gallic Acid Tris-Caffeine hexahydrate top
Crystal data top
C7H6O5·3C8H10N4O2·6H2OF(000) = 908
Mr = 860.81Dx = 1.501 Mg m3
Monoclinic, PcMo Kα radiation, λ = 0.71073 Å
a = 16.5434 (3) ÅCell parameters from 27647 reflections
b = 6.79456 (11) Åθ = 3.0–29.6°
c = 18.1390 (4) ŵ = 0.12 mm1
β = 110.865 (2)°T = 150 K
V = 1905.21 (7) Å3Plate, clear colourless
Z = 20.66 × 0.37 × 0.06 mm
Data collection top
Rigaku Oxford Diffraction Xcalibur, Atlas, Gemini ultra
diffractometer
8931 reflections with I > 2σ(I)
Detector resolution: 10.3968 pixels mm-1Rint = 0.029
ω scansθmax = 29.6°, θmin = 3.0°
Absorption correction: analytical
(CrysAlisPro; Rigaku OD, 2015)
h = 2122
Tmin = 0.946, Tmax = 0.994k = 99
38532 measured reflectionsl = 2524
9519 independent reflections
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.033 w = 1/[σ2(Fo2) + (0.051P)2 + 0.2608P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.086(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.24 e Å3
9519 reflectionsΔρmin = 0.23 e Å3
645 parametersAbsolute structure: Flack x determined using 4000 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
2 restraintsAbsolute structure parameter: 0.1 (2)
Primary atom site location: dual
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O120.64601 (10)0.3426 (2)0.43298 (9)0.0237 (3)
O740.39816 (11)0.9622 (2)0.29064 (9)0.0249 (3)
O100.53021 (10)0.3054 (3)0.63346 (9)0.0250 (3)
O720.66076 (10)0.8227 (3)0.48111 (10)0.0279 (3)
O1020.71299 (11)0.3149 (3)0.74098 (9)0.0259 (3)
O110.66635 (9)0.2955 (2)0.58370 (9)0.0241 (3)
O320.19013 (10)0.3831 (2)0.67800 (9)0.0257 (3)
O340.00090 (10)0.4828 (2)0.42738 (9)0.0259 (3)
O541.06258 (11)0.9604 (3)0.70872 (10)0.0289 (3)
O10.33315 (11)0.4973 (3)0.29402 (10)0.0292 (4)
O1000.61941 (12)0.6181 (3)0.77785 (10)0.0266 (3)
O1050.44257 (11)0.7234 (3)0.69929 (10)0.0288 (3)
O521.14078 (10)0.9016 (3)0.49147 (10)0.0300 (4)
O20.27018 (10)0.4707 (3)0.38411 (10)0.0300 (4)
O1040.38756 (11)0.3238 (3)0.66710 (11)0.0312 (4)
O1010.74791 (12)0.9351 (3)0.79622 (11)0.0325 (4)
N270.09392 (11)0.4384 (3)0.55358 (11)0.0200 (3)
N410.88046 (12)1.0593 (3)0.59097 (11)0.0210 (3)
N230.09763 (11)0.5534 (3)0.63666 (10)0.0203 (3)
N670.52922 (11)0.8905 (3)0.38714 (11)0.0201 (3)
N210.13658 (11)0.5677 (3)0.50514 (10)0.0187 (3)
N610.32462 (12)0.9330 (3)0.42452 (11)0.0216 (4)
N630.41353 (12)0.8759 (3)0.54870 (11)0.0221 (4)
O1030.86742 (14)0.4935 (4)0.77642 (12)0.0486 (6)
N451.00201 (12)0.9877 (3)0.46922 (11)0.0213 (4)
N471.10076 (11)0.9323 (3)0.59887 (11)0.0221 (4)
N430.85646 (11)1.0770 (3)0.46163 (11)0.0223 (4)
N250.05332 (11)0.4685 (3)0.66583 (10)0.0200 (3)
N650.54639 (11)0.8526 (3)0.52143 (10)0.0193 (3)
C90.49273 (13)0.4032 (3)0.39853 (12)0.0182 (4)
C280.01160 (13)0.4814 (3)0.49805 (12)0.0185 (4)
C680.43992 (14)0.9264 (3)0.36060 (12)0.0193 (4)
C640.45928 (13)0.8801 (3)0.49996 (12)0.0188 (4)
C50.43204 (13)0.3818 (3)0.50144 (12)0.0185 (4)
C220.16156 (14)0.5854 (3)0.56754 (12)0.0204 (4)
C40.42193 (13)0.4139 (3)0.42310 (12)0.0180 (4)
C260.11628 (13)0.4278 (3)0.63532 (12)0.0198 (4)
C30.33445 (14)0.4627 (3)0.36677 (12)0.0202 (4)
C420.82336 (14)1.0955 (3)0.51858 (13)0.0227 (4)
C620.33233 (14)0.9082 (3)0.49978 (13)0.0241 (4)
C60.51354 (13)0.3398 (3)0.55560 (12)0.0189 (4)
C290.04957 (13)0.5192 (3)0.53528 (12)0.0181 (4)
C240.02878 (13)0.5128 (3)0.61509 (12)0.0182 (4)
C80.57394 (13)0.3606 (3)0.45261 (12)0.0184 (4)
C690.40732 (13)0.9150 (3)0.42277 (12)0.0185 (4)
C70.58546 (13)0.3319 (3)0.53187 (12)0.0183 (4)
C490.95774 (13)1.0134 (3)0.58130 (13)0.0190 (4)
C481.04131 (14)0.9686 (3)0.63709 (13)0.0217 (4)
C461.08429 (14)0.9386 (3)0.51791 (13)0.0219 (4)
C300.19092 (13)0.5917 (3)0.42252 (12)0.0208 (4)
H30A0.1953140.4658260.3949770.031*
H30B0.1652530.6905180.3981380.031*
H30C0.2487430.6349080.4188440.031*
C440.94005 (13)1.0249 (3)0.50165 (12)0.0197 (4)
C660.58361 (14)0.8529 (3)0.46485 (13)0.0206 (4)
C710.60075 (14)0.8227 (3)0.60429 (13)0.0258 (4)
H71A0.5788300.9032480.6379240.039*
H71B0.6603640.8613990.6123520.039*
H71C0.5994110.6835890.6180360.039*
C310.07288 (15)0.4634 (4)0.75120 (13)0.0263 (4)
H31A0.0497800.3419200.7651620.039*
H31B0.0462610.5772000.7667810.039*
H31C0.1356920.4676600.7787600.039*
C510.98219 (16)0.9950 (4)0.38378 (14)0.0280 (5)
H51A1.0287451.0639880.3728860.042*
H51B0.9275121.0651120.3584580.042*
H51C0.9770810.8606910.3629010.042*
C500.86261 (17)1.0583 (4)0.66409 (15)0.0284 (5)
C330.16380 (14)0.4060 (4)0.52176 (14)0.0259 (5)
H33A0.1487330.2943530.4851770.039*
H33B0.2180500.3778800.5652710.039*
H33C0.1708500.5244150.4937880.039*
C531.19054 (14)0.8887 (4)0.64940 (15)0.0301 (5)
H53A1.2254541.0086080.6569300.045*
H53B1.2142300.7876980.6242160.045*
H53C1.1917370.8405790.7007190.045*
C730.57111 (16)0.8896 (4)0.32820 (15)0.0292 (5)
H73A0.5732610.7545930.3099620.044*
H73B0.6300550.9412620.3519050.044*
H73C0.5380020.9723130.2833480.044*
H50.3845 (19)0.391 (4)0.5203 (16)0.022 (6)*
H90.4873 (17)0.424 (4)0.3426 (16)0.017 (6)*
H220.220 (2)0.629 (4)0.5596 (17)0.030 (7)*
H10.282 (2)0.521 (5)0.2629 (19)0.035 (8)*
H120.631 (2)0.369 (4)0.3832 (19)0.031 (7)*
H620.284 (2)0.912 (5)0.5170 (18)0.035 (8)*
H100.482 (3)0.308 (6)0.641 (2)0.061 (11)*
C700.24418 (15)0.9659 (4)0.35795 (14)0.0265 (4)
H70A0.1948770.9475550.3751990.040*
H70B0.2401860.8719750.3158130.040*
H70C0.2435101.1004110.3381990.040*
H420.767 (2)1.131 (4)0.5092 (18)0.033 (7)*
H110.669 (2)0.304 (5)0.630 (2)0.041 (9)*
H10G0.392 (2)0.449 (5)0.6864 (19)0.036 (8)*
H10E0.425 (3)0.802 (6)0.728 (3)0.062 (11)*
H10F0.436 (2)0.781 (6)0.654 (2)0.053 (10)*
H10A0.718 (2)0.192 (6)0.760 (2)0.056 (10)*
H10I0.781 (2)0.915 (5)0.850 (2)0.039 (8)*
H10C0.568 (3)0.622 (6)0.746 (2)0.055 (11)*
H10D0.634 (2)0.518 (5)0.7604 (19)0.034 (8)*
H10B0.763 (2)0.367 (5)0.7558 (19)0.033 (8)*
H10K0.905 (3)0.515 (7)0.816 (3)0.076 (14)*
H10L0.881 (3)0.528 (6)0.738 (3)0.072 (13)*
H10H0.389 (3)0.243 (7)0.709 (3)0.077 (13)*
H10J0.714 (3)0.832 (6)0.788 (2)0.057 (11)*
H50A0.868 (2)0.928 (5)0.683 (2)0.044 (9)*
H50B0.803 (3)1.094 (6)0.651 (2)0.063 (11)*
H50C0.902 (3)1.156 (5)0.701 (2)0.055 (10)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O120.0148 (7)0.0379 (8)0.0204 (7)0.0037 (6)0.0089 (6)0.0030 (6)
O740.0245 (8)0.0298 (7)0.0219 (7)0.0003 (6)0.0102 (6)0.0024 (6)
O100.0172 (7)0.0413 (9)0.0174 (7)0.0025 (6)0.0073 (6)0.0042 (6)
O720.0165 (7)0.0332 (8)0.0358 (9)0.0021 (6)0.0117 (6)0.0004 (7)
O1020.0174 (8)0.0367 (9)0.0231 (7)0.0010 (7)0.0065 (6)0.0007 (7)
O110.0138 (7)0.0391 (9)0.0191 (7)0.0056 (6)0.0055 (6)0.0018 (6)
O320.0144 (7)0.0329 (8)0.0264 (8)0.0030 (6)0.0030 (6)0.0036 (6)
O340.0196 (7)0.0384 (9)0.0206 (7)0.0012 (6)0.0081 (6)0.0031 (6)
O540.0235 (8)0.0373 (8)0.0233 (8)0.0024 (7)0.0049 (7)0.0005 (7)
O10.0149 (7)0.0485 (10)0.0214 (7)0.0049 (7)0.0031 (6)0.0077 (7)
O1000.0244 (9)0.0339 (9)0.0214 (8)0.0019 (7)0.0081 (7)0.0022 (7)
O1050.0314 (9)0.0353 (9)0.0236 (8)0.0057 (7)0.0145 (7)0.0029 (7)
O520.0197 (8)0.0368 (9)0.0378 (9)0.0017 (6)0.0154 (7)0.0023 (7)
O20.0150 (7)0.0467 (10)0.0282 (8)0.0038 (7)0.0075 (7)0.0045 (7)
O1040.0268 (8)0.0426 (10)0.0290 (8)0.0020 (7)0.0159 (7)0.0003 (8)
O1010.0279 (9)0.0394 (10)0.0288 (9)0.0025 (8)0.0085 (7)0.0033 (7)
N270.0135 (8)0.0242 (8)0.0233 (9)0.0001 (6)0.0078 (7)0.0025 (6)
N410.0172 (8)0.0218 (8)0.0262 (9)0.0010 (7)0.0104 (7)0.0017 (7)
N230.0164 (8)0.0250 (8)0.0203 (8)0.0000 (7)0.0074 (7)0.0001 (7)
N670.0185 (9)0.0222 (8)0.0236 (8)0.0005 (7)0.0122 (7)0.0006 (7)
N210.0128 (8)0.0232 (8)0.0200 (8)0.0001 (6)0.0058 (7)0.0005 (6)
N610.0144 (8)0.0278 (9)0.0245 (9)0.0001 (7)0.0094 (7)0.0000 (7)
N630.0190 (9)0.0281 (9)0.0224 (8)0.0001 (7)0.0111 (7)0.0008 (7)
O1030.0296 (10)0.0955 (18)0.0216 (9)0.0251 (11)0.0102 (8)0.0029 (10)
N450.0164 (8)0.0253 (9)0.0234 (9)0.0010 (7)0.0086 (7)0.0011 (7)
N470.0121 (8)0.0251 (8)0.0270 (9)0.0005 (7)0.0046 (7)0.0026 (7)
N430.0155 (9)0.0225 (8)0.0268 (9)0.0010 (6)0.0047 (7)0.0012 (7)
N250.0146 (8)0.0250 (8)0.0187 (8)0.0013 (6)0.0038 (7)0.0010 (6)
N650.0147 (8)0.0231 (8)0.0210 (8)0.0011 (6)0.0073 (7)0.0015 (7)
C90.0166 (9)0.0211 (9)0.0177 (9)0.0003 (7)0.0073 (8)0.0000 (7)
C280.0156 (9)0.0194 (9)0.0208 (9)0.0013 (7)0.0066 (8)0.0014 (7)
C680.0194 (10)0.0170 (9)0.0242 (10)0.0007 (7)0.0110 (8)0.0004 (7)
C640.0168 (9)0.0189 (9)0.0223 (10)0.0015 (7)0.0090 (8)0.0010 (7)
C50.0139 (9)0.0215 (9)0.0217 (10)0.0007 (7)0.0084 (8)0.0001 (7)
C220.0156 (10)0.0245 (10)0.0221 (10)0.0005 (8)0.0078 (8)0.0002 (8)
C40.0151 (9)0.0179 (9)0.0211 (9)0.0003 (7)0.0066 (8)0.0006 (7)
C260.0152 (9)0.0204 (9)0.0227 (10)0.0003 (7)0.0053 (8)0.0022 (8)
C30.0161 (9)0.0222 (9)0.0214 (10)0.0000 (7)0.0056 (8)0.0008 (8)
C420.0134 (10)0.0236 (10)0.0307 (11)0.0011 (7)0.0076 (8)0.0013 (8)
C620.0176 (10)0.0329 (11)0.0252 (10)0.0001 (8)0.0118 (8)0.0008 (8)
C60.0187 (9)0.0199 (9)0.0190 (9)0.0013 (7)0.0078 (8)0.0009 (7)
C290.0128 (9)0.0200 (9)0.0206 (9)0.0006 (7)0.0050 (7)0.0001 (7)
C240.0146 (9)0.0180 (9)0.0218 (10)0.0000 (7)0.0063 (8)0.0003 (7)
C80.0158 (9)0.0196 (9)0.0222 (10)0.0003 (7)0.0097 (8)0.0005 (7)
C690.0151 (9)0.0193 (9)0.0225 (10)0.0004 (7)0.0086 (8)0.0003 (7)
C70.0145 (9)0.0196 (9)0.0193 (9)0.0016 (7)0.0042 (7)0.0001 (7)
C490.0132 (9)0.0206 (9)0.0238 (10)0.0003 (7)0.0072 (8)0.0015 (7)
C480.0178 (10)0.0189 (9)0.0282 (11)0.0002 (8)0.0078 (9)0.0021 (8)
C460.0167 (10)0.0204 (9)0.0291 (11)0.0007 (7)0.0089 (8)0.0022 (8)
C300.0144 (9)0.0281 (10)0.0175 (9)0.0007 (7)0.0028 (8)0.0003 (8)
C440.0159 (9)0.0184 (9)0.0253 (10)0.0011 (7)0.0078 (8)0.0025 (8)
C660.0187 (9)0.0181 (9)0.0271 (10)0.0000 (7)0.0107 (8)0.0003 (8)
C710.0199 (10)0.0316 (11)0.0235 (10)0.0017 (9)0.0048 (8)0.0005 (9)
C310.0205 (10)0.0381 (12)0.0182 (10)0.0022 (9)0.0044 (8)0.0024 (9)
C510.0279 (12)0.0360 (12)0.0226 (10)0.0008 (9)0.0119 (9)0.0024 (9)
C500.0280 (12)0.0328 (12)0.0312 (12)0.0035 (10)0.0190 (10)0.0003 (10)
C330.0148 (10)0.0335 (11)0.0327 (12)0.0018 (8)0.0125 (9)0.0035 (9)
C530.0146 (10)0.0324 (11)0.0376 (13)0.0031 (8)0.0023 (9)0.0039 (10)
C730.0266 (12)0.0373 (12)0.0315 (12)0.0016 (9)0.0198 (10)0.0014 (10)
C700.0175 (10)0.0350 (11)0.0255 (10)0.0019 (9)0.0056 (8)0.0018 (9)
Geometric parameters (Å, º) top
O12—C81.366 (2)N43—C441.360 (3)
O12—H120.86 (3)N25—C261.370 (3)
O74—C681.234 (3)N25—C241.376 (3)
O10—C61.359 (2)N25—C311.465 (3)
O10—H100.86 (4)N65—C641.365 (3)
O72—C661.221 (3)N65—C661.372 (3)
O102—H10A0.89 (4)N65—C711.465 (3)
O102—H10B0.85 (4)C9—C41.396 (3)
O11—C71.356 (2)C9—C81.383 (3)
O11—H110.83 (4)C9—H91.00 (3)
O32—C261.229 (3)C28—C291.426 (3)
O34—C281.224 (3)C68—C691.415 (3)
O54—C481.221 (3)C64—C691.378 (3)
O1—C31.333 (3)C5—C41.388 (3)
O1—H10.85 (3)C5—C61.386 (3)
O100—H10C0.83 (4)C5—H50.97 (3)
O100—H10D0.82 (4)C22—H220.97 (3)
O105—H10E0.86 (5)C4—C31.481 (3)
O105—H10F0.88 (4)C42—H420.92 (3)
O52—C461.219 (3)C62—H620.96 (3)
O2—C31.213 (3)C6—C71.403 (3)
O104—H10G0.91 (3)C29—C241.364 (3)
O104—H10H0.93 (5)C8—C71.395 (3)
O101—H10I0.94 (4)C49—C481.425 (3)
O101—H10J0.88 (4)C49—C441.370 (3)
N27—C281.406 (3)C30—H30A0.9800
N27—C261.396 (3)C30—H30B0.9800
N27—C331.481 (3)C30—H30C0.9800
N41—C421.339 (3)C71—H71A0.9800
N41—C491.387 (3)C71—H71B0.9800
N41—C501.458 (3)C71—H71C0.9800
N23—C221.339 (3)C31—H31A0.9800
N23—C241.358 (3)C31—H31B0.9800
N67—C681.403 (3)C31—H31C0.9800
N67—C661.399 (3)C51—H51A0.9800
N67—C731.467 (3)C51—H51B0.9800
N21—C221.342 (3)C51—H51C0.9800
N21—C291.385 (3)C50—H50A0.94 (3)
N21—C301.456 (3)C50—H50B0.96 (4)
N61—C621.336 (3)C50—H50C1.00 (4)
N61—C691.385 (3)C33—H33A0.9800
N61—C701.461 (3)C33—H33B0.9800
N63—C641.353 (3)C33—H33C0.9800
N63—C621.338 (3)C53—H53A0.9800
O103—H10K0.78 (5)C53—H53B0.9800
O103—H10L0.84 (5)C53—H53C0.9800
N45—C461.374 (3)C73—H73A0.9800
N45—C441.375 (3)C73—H73B0.9800
N45—C511.466 (3)C73—H73C0.9800
N47—C481.412 (3)C70—H70A0.9800
N47—C461.396 (3)C70—H70B0.9800
N47—C531.471 (3)C70—H70C0.9800
N43—C421.336 (3)
C8—O12—H12107 (2)N23—C24—C29112.27 (18)
C6—O10—H10108 (3)C29—C24—N25122.19 (18)
H10A—O102—H10B109 (3)O12—C8—C9123.47 (18)
C7—O11—H11111 (2)O12—C8—C7116.40 (18)
C3—O1—H1111 (2)C9—C8—C7120.14 (18)
H10C—O100—H10D97 (3)N61—C69—C68132.3 (2)
H10E—O105—H10F109 (4)C64—C69—N61104.82 (17)
H10G—O104—H10H105 (3)C64—C69—C68122.86 (19)
H10I—O101—H10J99 (3)O11—C7—C6121.96 (18)
C28—N27—C33116.29 (17)O11—C7—C8118.61 (18)
C26—N27—C28126.45 (17)C8—C7—C6119.43 (18)
C26—N27—C33117.24 (17)N41—C49—C48131.5 (2)
C42—N41—C49106.10 (18)C44—C49—N41105.08 (18)
C42—N41—C50126.3 (2)C44—C49—C48123.34 (19)
C49—N41—C50127.5 (2)O54—C48—N47121.84 (19)
C22—N23—C24103.11 (17)O54—C48—C49127.2 (2)
C68—N67—C73117.64 (18)N47—C48—C49110.97 (19)
C66—N67—C68126.75 (17)O52—C46—N45121.3 (2)
C66—N67—C73115.61 (18)O52—C46—N47121.2 (2)
C22—N21—C29106.10 (17)N45—C46—N47117.47 (18)
C22—N21—C30126.55 (18)N21—C30—H30A109.5
C29—N21—C30127.34 (17)N21—C30—H30B109.5
C62—N61—C69106.06 (18)N21—C30—H30C109.5
C62—N61—C70126.25 (19)H30A—C30—H30B109.5
C69—N61—C70127.66 (18)H30A—C30—H30C109.5
C62—N63—C64103.07 (18)H30B—C30—H30C109.5
H10K—O103—H10L110 (5)N43—C44—N45126.21 (19)
C46—N45—C44119.25 (18)N43—C44—C49111.87 (18)
C46—N45—C51119.00 (18)C49—C44—N45121.92 (18)
C44—N45—C51121.74 (18)O72—C66—N67121.06 (19)
C48—N47—C53117.03 (19)O72—C66—N65121.9 (2)
C46—N47—C48127.02 (18)N65—C66—N67117.06 (18)
C46—N47—C53115.92 (18)N65—C71—H71A109.5
C42—N43—C44103.33 (18)N65—C71—H71B109.5
C26—N25—C24119.03 (17)N65—C71—H71C109.5
C26—N25—C31120.56 (18)H71A—C71—H71B109.5
C24—N25—C31120.40 (17)H71A—C71—H71C109.5
C64—N65—C66119.72 (17)H71B—C71—H71C109.5
C64—N65—C71120.76 (17)N25—C31—H31A109.5
C66—N65—C71119.51 (18)N25—C31—H31B109.5
C4—C9—H9122.5 (15)N25—C31—H31C109.5
C8—C9—C4119.88 (18)H31A—C31—H31B109.5
C8—C9—H9117.6 (15)H31A—C31—H31C109.5
O34—C28—N27120.75 (18)H31B—C31—H31C109.5
O34—C28—C29127.67 (19)N45—C51—H51A109.5
N27—C28—C29111.58 (17)N45—C51—H51B109.5
O74—C68—N67121.51 (19)N45—C51—H51C109.5
O74—C68—C69126.7 (2)H51A—C51—H51B109.5
N67—C68—C69111.75 (18)H51A—C51—H51C109.5
N63—C64—N65126.15 (19)H51B—C51—H51C109.5
N63—C64—C69112.08 (18)N41—C50—H50A108 (2)
N65—C64—C69121.77 (18)N41—C50—H50B107 (3)
C4—C5—H5122.4 (16)N41—C50—H50C108 (2)
C6—C5—C4119.37 (19)H50A—C50—H50B107 (3)
C6—C5—H5118.2 (16)H50A—C50—H50C115 (3)
N23—C22—N21113.42 (19)H50B—C50—H50C111 (3)
N23—C22—H22126.9 (17)N27—C33—H33A109.5
N21—C22—H22119.4 (17)N27—C33—H33B109.5
C9—C4—C3121.08 (18)N27—C33—H33C109.5
C5—C4—C9120.66 (18)H33A—C33—H33B109.5
C5—C4—C3118.26 (18)H33A—C33—H33C109.5
O32—C26—N27120.64 (19)H33B—C33—H33C109.5
O32—C26—N25121.57 (19)N47—C53—H53A109.5
N25—C26—N27117.80 (18)N47—C53—H53B109.5
O1—C3—C4112.93 (18)N47—C53—H53C109.5
O2—C3—O1122.85 (19)H53A—C53—H53B109.5
O2—C3—C4124.22 (19)H53A—C53—H53C109.5
N41—C42—H42123 (2)H53B—C53—H53C109.5
N43—C42—N41113.62 (19)N67—C73—H73A109.5
N43—C42—H42123 (2)N67—C73—H73B109.5
N61—C62—N63113.97 (19)N67—C73—H73C109.5
N61—C62—H62122.8 (19)H73A—C73—H73B109.5
N63—C62—H62123.2 (19)H73A—C73—H73C109.5
O10—C6—C5123.93 (18)H73B—C73—H73C109.5
O10—C6—C7115.58 (18)N61—C70—H70A109.5
C5—C6—C7120.49 (19)N61—C70—H70B109.5
N21—C29—C28131.99 (19)N61—C70—H70C109.5
C24—C29—N21105.09 (17)H70A—C70—H70B109.5
C24—C29—C28122.92 (18)H70A—C70—H70C109.5
N23—C24—N25125.54 (18)H70B—C70—H70C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O32i0.85 (3)1.86 (3)2.672 (2)161 (3)
O10—H10···O1040.86 (4)1.79 (4)2.643 (2)174 (4)
O11—H11···O100.83 (3)2.32 (4)2.709 (2)109 (3)
O11—H11···O1020.83 (4)1.88 (4)2.680 (2)161 (3)
O12—H12···O100i0.86 (3)1.86 (3)2.702 (2)166 (3)
O100—H10C···O1050.83 (4)2.07 (4)2.851 (3)157 (4)
O100—H10D···O100.82 (4)2.74 (3)3.286 (2)126 (3)
O100—H10D···O1020.82 (4)2.02 (4)2.798 (3)158 (3)
O101—H10I···N43ii0.94 (4)1.97 (4)2.898 (3)170 (3)
O101—H10J···O1000.88 (4)2.09 (4)2.960 (3)170 (4)
O102—H10A···O101iii0.89 (4)1.87 (4)2.754 (3)169 (4)
O102—H10B···O1030.85 (4)1.85 (4)2.691 (3)173 (3)
O103—H10K···O34iv0.78 (5)2.06 (5)2.832 (3)168 (5)
O103—H10L···N23v0.84 (5)1.99 (5)2.823 (3)168 (4)
O104—H10G···O1vi0.91 (3)2.50 (3)3.011 (2)116 (2)
O104—H10G···O1050.91 (3)2.03 (3)2.857 (3)151 (3)
O104—H10H···O74vi0.93 (5)2.00 (5)2.924 (2)171 (4)
O105—H10E···O74ii0.86 (5)2.11 (5)2.952 (2)169 (4)
O105—H10F···N630.88 (4)1.92 (4)2.798 (2)173 (4)
C22—H22···O72vii0.97 (3)2.38 (3)3.227 (3)146 (2)
C30—H30C···O12vii0.982.713.247 (3)115
C31—H31C···O2vi0.982.403.326 (3)158
C42—H42···O12viii0.92 (3)2.45 (3)3.254 (3)146 (3)
C42—H42···O720.92 (3)2.66 (3)3.136 (3)113 (2)
C62—H62···O52vii0.96 (3)2.24 (3)3.119 (3)151 (3)
Symmetry codes: (i) x, y+1, z1/2; (ii) x, y+2, z+1/2; (iii) x, y1, z; (iv) x+1, y+1, z+1/2; (v) x+1, y, z; (vi) x, y+1, z+1/2; (vii) x1, y, z; (viii) x, y+1, z.
 

Funding information

Funding for this research was provided by: Seventh Framework Programme, FP7 People: Marie-Curie Actions (grant No. 256547 to U. Baisch).

References

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